A rare case of acute myeloid leukemia in a 4-day-old neonate with concurrent trisomy 21 and trisomy 18

Abstract

Neonates with trisomy 21 often present with hemato-lymphoid neoplasms, especially in the first 5 years of their life. In such neonates, acute myeloid leukemia, if at all occurs, is preceded by a preleukemic condition known as transient abnormal myelopoiesis (TAM), comprising blast proliferation, which is often self-limiting and rarely may progress into a full-blown case of acute leukemia. We report a case of a neonate with suspected acute leukemia, referred from a Government Medical College for immunophenotyping by flow cytometry, which we reported as acute leukemia along with a possibility of TAM. As karyotyping was not feasible due to sample degradation, however, fluorescence in situ hybridization was performed as a part of further work-up, which surprisingly detected both trisomy 21 and trisomy 18. Unfortunately, the neonate succumbed to respiratory distress and cardiac arrest on day 7, before initiation of therapy. The simultaneous occurrence of trisomy 21 and trisomy 18 in a neonate with suspected hemato-lymphoid malignancy is a rare and noteworthy cytogenetic anomaly. This case underscores the critical role of flow cytometry and molecular diagnostics in neonatal leukemia evaluation.